The present invention relates to a system for enhancing release of acids into a wash from anhydride precursors found in the wash (e.g., an acyl anhydride) using esterases as activators for the anhydride precursors. In particular, acid release is enhanced under relatively neutral conditions (i.e., about pH 7).
Acids, e.g., carboxylic acids, have long been employed in numerous cleaning applications including the washing and prewashing of fabrics as well as in other applications such as hard surface cleaning. In these applications, the acids are used, for example, for buffering and enzyme stabilization.
Although acids are formed from the hydrolysis of anhydrides, this reaction is generally very slow under neutral conditions (i.e., about pH 7) and can be accelerated only by using harsher conditions such as very low (e.g., below pH 5) or very high (e.g., above pH 10) pH conditions.
In a related application, U.S. Ser. No. 841,395 to Kaiserman et al., applicants disclosed the use of enzyme activators to release bleach from bleach precursors. There was no teaching in that application regarding production of acids from anhydride precursors.
Accordingly, there is a need in the art for accelerating production of acids from anhydride precursors.
Unexpectedly, applicants have discovered a system whereby acids are released more quickly from acid precursors (i.e., anhydrides) using esterase enzymes (i.e., any enzyme having esterase activity). The acceleration of acid formation can be noted at all pH ranges relative to not using esterase at all, but is especially striking in that it allows acid to be formed from anhydride even at neutral pH ranges (i.e., pH 7) where it was not previously believed that acid release from these acid precursors was achievable. That is formation of the acid from anhydrides at neutral pH was previously believed nonexistent or negligible at best.
The present system may be used in liquid or powder detergent systems such as are well known to those skilled in the art.